Tutor profile: Matt L.

A 65 year old female with gastric adenocarcinoma presents to the ER with shortness of breath that started suddenly this morning. Her O2 saturation is 82% and she is tachypneic. Arterial blood gas shows an increased A-a gradient. She is started on high Flo nasal canula supplemental oxygen. What is the most appropriate next step in management of this patient?

Stat CT scan of her chest with intravenous contrast to rule out a pulmonary embolism which should be high on the differential diagnosis given her history of malignancy and the sudden onset of symptoms.

Why does an organic compound composed of a long chain of carbon atoms have a higher melting and boiling point than a similar molecule with less carbons linked up linearly?

As the length of the carbon chain increases in alkanes, the cumulative effect that the carbon atoms have on neighboring carbon atoms increases. This increased force between molecules requires higher levels or energy to change the phase of the compound, I.e. melting and boiling.

Please define gravity.

Gravity a the physical force experienced by all object in the universe. It causes all objects with a mass to influence and be influenced by all other objects with a mass and results in their tendency to move in each others direction with a force magnitude inversely proportional to the distance between these two objects.